Herpes zoster

Definition

Herpes zoster (shingles) is a painful, blistering skin rash due to acute infection with the varicella-zoster virus, the virus that causes chickenpox.

See also: Ramsay Hunt syndrome

Alternative Names

Shingles

Causes, incidence, and risk factors

After you get chickenpox, the virus falls asleep (becomes dormant) in certain nerves in the body. Shingles occurs after the virus becomes reactive in these nerves after many years.

The reason the virus suddenly become active again is not clear. Often only one attack occurs.

If an adult or child is exposed to the herpes zoster virus and has not had chickenpox as a child or received the chickenpox vaccine, a severe case of chickenpox may develop, rather than shingles.

Herpes zoster can be contagious through direct contact in an individual who has not had chickenpox, and therefore has no immunity. Herpes zoster may affect any age group, but it is much more common in adults over 60 years old, in children who had chickenpox before the age of one year, and in individuals whose immune system is weakened.

Symptoms

The first symptom is usually one-sided pain, tingling, or burning. The pain and burning may be severe.

Red patches on the skin form, followed by small blisters that look very similar to early chickenpox. The blisters break, forming small ulcers that begin to dry and form crusts. The crusts fall off in 2 to 3 weeks.

The rash usually involves a narrow area from the spine around to the front of the belly area or chest. It may involve face, eyes, mouth, and ears.

Additional symptoms may include:

• Abdominal pain
• Chills
• Difficulty moving some of the muscles in the face
• Drooping eyelid (ptosis)
• Fever
• General ill-feeling
• Genital lesions
• Headache
• Hearing loss
• Joint pain
• Loss of eye motion (ophthalmoplegia)
• Swollen glands (lymph nodes)
• Taste problems
• Vision problems

Signs and tests

Your doctor can make the diagnose by looking at your skin and asking questions about your medical history.

Tests are rarely needed, but may include taking a skin sample to see if the skin is infected with the virus that causes shingles.

Lab tests may show an increase in white blood cells and antibodies to the chickenpox virus but cannot confirm that the rash is due to shingles.